Bushnell Northstar 78-7830 User manual

Instruction
Manual
COMPUTERIZED STAR LOCATOR
78-7860 60mm Refractor
78-7880 80mm Refractor
78-7830 3” Reflector
78-7845 4.5” reflector
Lit. #: 91-0219/03-01

2.

Where DO I START?
Your Bushnell telescope can bring the wonders of the universe to your eye. While
this manual is intended to assist you in the set-up and basic use of this instrument,
it does not cover everything you might like to know about astronomy. Although
Northstar will give a respectable tour of the night sky, it is recommended you get a
very simple star chart and a flashlight with a red bulb or red cellophane over the
end. For objects other than stars and constellations, a basic guide to astronomy is
a must. Some recommended sources appear on our website at
www.bushnell.com. Also on our website will be current events in the sky for
suggested viewing. But, some of the standbys that you can see are:
The Moon—a wonderful view of our lunar neighbor can be enjoyed with any
magnification. Try viewing at different phases of the moon. Lunar highlands, lunar
maria (lowlands called "seas" for their dark coloration), craters, ridges and
mountains will astound you.
Saturn—even at the lowest power you should be able to see Saturn’s rings and
moons. This is one of the most satisfying objects in the sky to see simply because
it looks like it does in pictures. Imagine seeing what you’ve seen in textbooks or
NASA images from your backyard!
Jupiter—the largest planet in our solar system is spectacular. Most noted features
are its dark stripes or bands both above and below its equator. These are the north
and south equatorial belts. Also interesting are Jupiter’s four major moons. Pay
close attention to their positions from night to night. They appear to be lined up on
either side of Jupiter.
Mars—The Great Red Planet appears as a reddish-orange disk. Look at different
times of the year and try to catch a glimpse of the white polar ice caps.
Venus—just like the moon, Venus changed phases from month to month. Some views
of brilliant Venus appear as if you were looking at a distant crescent moon.
Nebulae—The Great Orion Nebula is a very well known night sky object. This and many
others are brought to you by this telescope.
Star Clusters—View millions of stars densely packed in a cluster that resembles a ball.
Galaxies—One of the greatest and most interesting galaxies is our neighbor the
Andromeda Galaxy. Enjoy this and many others.
3.

78-7880 80mm Refractor
Parts Diagrams
78-7860 60mm Refractor
IMPORTANT:
READ THROUGH
ASSEMBLY INSTRUCTION
BEFORE YOUASSEMBLE
YOUR TELESCOPE.
4.

78-7830 3” Reflector
78-7845 4.5” reflector
Parts Diagrams (Continued)
1. Wide Field Finderscope
2. 1.25" Format Eyepiece
3. Penta Mirror
4. Rack and Pinion Focusing Mechanism
5. Accessory Tray Brace
6. Quick-Release Tripod Leg Lever
7. Quick-Release Accessory Tray
8. Onboard Computer
9. Main Telescope Tube
10. Quick-Release Adjustable Aluminum Tripod
Telescope Parts Diagram
5.

78-7860 60mm
Refractor
78-7880 80mm
Refractor
Quick Assembly Diagram
6.

• Adjustable Aluminum Tripod Assembly (Three Legs)
• Quick Release Accessory Tray
• Northstar Computerized Star Locator Base
•Northstar Telescope Tube w/ finger attachment nuts
• Wide Field Finderscope
• 20mm 1.25" Diameter Eyepiece
• 4mm 1.25" Diameter Eyepiece
• Barlow Lens
• Erecting Lens (not included with model 78-7830)
•Penta Mirror (not included with model 78-7830)
78-7830 3” Reflector
78-7845 4.5” reflector
Parts List
2
1
7.
Quick Assembly Diagram

Detailed Assembly
No tools are required for assembly of your telescope.
Remove all components from the carton and identify all components. It is a good idea to lay all the parts out in front of
you before assembly. Since your telescope is a precision optical system the parts require careful handling—particularly
the onboard computer, telescope, eyepieces, and various accessory lenses.
SET-UP TRIPOD AND ACCESSORY TRAY
1. Stand Northstar Computerized Star Locator Assembly and attached tripod legs in
the upright position. Spread tripod legs to a comfortable distance.
2. Fold down the accessory tray braces and place the Quick Release Accessory
Tray on top of braces. (See Quick Assembly Diagram)
3. Turn accessory tray until it snaps into place.
4. Adjust tripod leg height to suit by opening tripod leg lever and extending tripod legs
to desired height. Clamp Tripod Leg lever closed when complete.
ATTACH TELESCOPE TUBE
1. Locate Main Telescope Tube.
2. Remove Telescope Tube Thumb Nuts from side of Telescope Tube.
(See Quick Assembly Diagram)
3. Position Main Telescope Tube Attachment Bolts through Telescope Tube Bracket at the top of the N o r t h s t a r
Computerized Star LocatorAssembly. Make sure the telescope is pointing in the correct direction. (Logo on telescope
tube should be right side-up.)
4. Reattach Telescope Tube Thumb Nuts to Main Telescope Tube Attachment Bolts once Main
Telescope Tube and Northstar Computerized Star Locator Assembly are assembled together.
ATTACH FINAL TELESCOPE ACCESSORIES
1. Locate Wide Field Finderscope.
For Refractor Telescopes: Northstar Refractor Telescope Models have Finderscope Mount
already attached to Main Telescope Tube. Simply place the Wide Field Finderscope into the Finderscope Mount by
backing out the Finderscope Adjustment Screws to allow Finderscope to be fully inserted into the Finderscope Mount.
NOTE: Finderscope should be facing forward (Large end nearest the lens end of the telescope tube).
For Reflector Telescopes: Remove Finderscope attachment nuts from Main Telescope Tube. Place Finderscope
Assembly over Finderscope Attachment Bolts and reattach Finderscope thumb nuts to Finderscope Mount Bolts.
NOTE: Finderscope should have large end of the finderscope facing open end of telescope tube.
2. Attach Low Power Eyepiece:
For Reflector Telescope Models: Insert lowest power eyepiece in the focusing mechanism
by backing out eyepiece set screw and inserting eyepiece fully.
For Refractor Telescope Models: Insert lowest power eyepiece into the penta mirror by
backing out eyepiece set screw, then insert penta mirror into the focusing tube of the Main Telescope Tube by backing
out focusing tube set screw.
3. Tighten all set screws to secure accessories.
4. Remove Objective Dust Cover and Finderscope Dust Cover Caps.
8.

MALIGNING FINDERSCOPE
Look through Main Telescope Tube and establish a well-defined target. (see focusing telescope section)
Looking through Wide Field Finderscope, alternate tightening each Finderscope Adjustment Screw until crosshairs of Wide
Field Finderscope are precisely centered on the same object already centered in Main Telescope Tube’s field of view.
Now, objects located first with the Wide Field Finderscope will be centered in the field of view of the main telescope.
MSELECTING AN EYEPIECE
MFOCUSING TELESCOPE
1. After selecting the desired eyepiece, aim main telescope tube at a land-based target at least 200 yards away
(e.g. Atelephone pole or building).
2. Fully extend focusing tube by turning Rack and Pinion Focusing Mechanism.
3. While looking through selected eyepiece (in this case the 20 mm), slowly retract focusing tube by turning Rack
and Pinion Focusing Mechanism until object comes into focus.
You should always start viewing with the lowest power eyepiece, which in this case is the 20 mm lens. Note: the base
power of each eyepiece is determined by the focal length of the telescope objective lens. A formula can be used to
determine the power of each eyepiece: telescope OBJECTIVE lens focal length divided by EYEPIECE focal length =
MAGNIFICATION (e.g. Using the 20 mm lens, a sample calculation could look like this: 750 mm / 20 = 38x or 38
power. Telescope models will vary in focal length.)
Included with this telescope is a Barlow lens. Barlow lenses are used to double or triple the power of your telescope.
Place your Barlow between the focusing tube and the eyepiece. Using the example above, your 3x Barlow lens would
give you a total power of 114x or 114 power. (38 x 3 = 114x or 114 power). The magnification calculation would look like
this: 750 mm /20mm = 38 power. 38 power x 3=114 power.
Detailed Assembly (continued)
Never Look Directly At The Sun With Your
Telescope Permanent Damage
To Your Eyes May Occur
❂
9.

MENJOYING YOUR NEW TELESCOPE
1. First determine your targeted object. Any bright object in the night sky is a good starting point.
One of the favorite starting points in astronomy is the moon. This is an object sure to please any
budding astronomer or experienced veteran. When you have developed proficiency at this level,
other objects become good targets. Saturn, Mars, Jupiter, and Venus are good second steps to take.
2. The first thing you need to do after assembling the telescope as planned is center the desired
object in the finderscope’s cross hairs. Provided you did a reasonable job aligning the finderscope, a
quick look through the main telescope tube at low power should reveal the same image. With the
lowest power eyepiece (the one with the largest number printed on it) you should be able to focus
the same image that you saw through the finderscope. Avoid the temptation to move directly to the
highest power. The low power eyepiece will give you a wider field of view, and brighter image—thus
making it very easy to find your target object. At this point with a focused image in both scopes,
you’ve passed the first obstacle. If you don’t see an image after attempting to focus it in, you
might consider aligning your finderscope again. Once you pass this step, you’ll will enjoy the time
spent ensuring a good alignment. Every object you center in the finderscope will be easily found in
the main telescope tube, which is important for continuing your exploration of the night sky.
3. The low power eyepieces are perfect for viewing the full moon, planets, star clusters, nebulae,
and even constellations. These should build your foundation. However, for more detail, try bumping
up in magnification to higher power eyepieces on some of these objects. During calm and crisp
nights, the light/dark separation line on the moon (called the "Terminator") is marvelous at high power.
You can see mountains, ridges and craters jump out at you due to the highlights. Similarly, you can
move up to higher magnifications on the planets and nebulae. Star clusters and stars are best viewed
through the low power no matter what.
4. The recurring astronomical theater we call the night sky is an ever-changing billboard. In other
words, not the same movie plays all the time. Rather, the positions of the stars change not only
hourly as they seem to rise and set, but also throughout the year. As the earth orbits the sun our
perspective on the stars changes on a yearly cycle about that orbit. The reason the sky seems to
move daily just as the sun and the moon "move" across our sky, is that the earth is rotating about its
axis. As a result you may notice that after a few minutes or a few seconds depending on what power
you are viewing at, the objects in your telescope will move. At higher magnifications especially, you
will notice that the moon or Jupiter will "race" right out of the field of view. To compensate, just move
your telescope to "track" it in the necessary path.
10.

MHELPFUL HINTS
1. Your telescope is a very sensitive instrument. For best results and fewer vibrations set
your telescope up on a level location on the ground rather than your concrete driveway or
your wooden deck. This will provide a more stable foundation for viewing, especially if
you’ve drawn a crowd with your new telescope.
2. If possible view from a location that has relatively few lights. This will allow you to see
much fainter objects. You’d be surprised how much more you’ll see from your local lake
or park when compared to a backyard in the city.
3. Using your telescope out a window is NEVER recommended.
4. View objects that are high in the sky if possible. Waiting until the object rises well
above the horizon will provide a brighter and crisper image. Objects on the horizon
are viewed through several layers of earth’s atmosphere. Ever wonder why the
moon appears orange as it sets on the horizon. It’s because you are looking through
a considerable more amount of atmosphere than you would directly overhead.
(Note: If objects high in the sky are distorted or wavy, you are probably viewing on
a very humid night.) During nights of unstable atmosphere, viewing through a
telescope can be frustrating if not impossible. Astronomers refer to crisp, clear nights
as nights of "good seeing."
11.

Button Functions
LCD DISPLAY
1. Computer Link
2. Scroll Up Button
3. Scroll Down Button
4. Back Button
5. Enter Button
6. LCD Display
7. On/Off/Dim Button
8. Battery Cover Door
9. Battery Cover Set Screw
Northstar Computer
Interface Diagram
The Liquid Crystal Display (LCD) is a two-line, sixteen character display. The LCD also has an electroluminescent
backlight for use during nighttime viewing with the Northstar Computerized Star Locator.
Back Button: This button functions to navigate to the previous level within the operating framework and/or back to the
previous level of input.
Enter Button: This button functions to select certain menu choices. By pressing the ENTER button Northstar will
advance to the selected level. When an object name or number is listed on the screen, the ENTER button can also be
pressed to display a scrolling text description of the object
Scroll Up Button: This button functions to scroll up through various menus within Northstar. Anytime you encounter
a blinking text/number option, the scroll button will display the various choices within that menu. (Note: To select an
option that you have scrolled to, just press the ENTER button.
Scroll Down Button: This button functions to scroll down through various menus within Northstar. Anytime you
encounter a blinking text/number option, the scroll button will display the various choices within that menu.
(Note: To select an option that you have scrolled to, just press the ENTER button.
On/Off/Dim: The On/Off Button will turn the Northstar Computerized Star Locator on and off. Once on, you can adjust
the level of LCD Backlight Illumination by pressing the On/Off/Dim Button to cycle through the brightness levels. To turn
the unit off, simply depress and hold the On/Off/Dim button for three seconds and release. (Note: The Northstar
Computerized Star Locator will automatically turn itself off after 20 minutes of inactivity.)
12.

MMODE OVERVIEW OF PRODUCT
Explore: The Explore Mode of Northstar provides the ability to explore various astronomical objects
categorized by object type. These objects would fall under one or more of the following types of objects:
Deep Sky, Planets, Constellations, and Stars. Each of these subheadings would also have subcategories
of objects beneath their menu structure. (See Menu Tree for full list of menu functions and options.)
Sky Tour: The Sky Tour Mode of Northstar provides the ability to take a quick tour of the best and brightest
objects for any given month of the year. If the date has been input into the system, the Sky Tour Mode will
automatically default to that month. Objects can be chosen by using the scroll up ordown arrows and pressing
ENTER. To find out more information about any given object press the enter button while that object is displayed
to see the scrolling text message.
Telescope: The Telescope Mode of Northstar provides real-time data on where the telescope is pointing.
Astronomical Coordinates for Right Ascension (RA) and Declination (DEC) as well as Altitude (ALT) andAzimuth
(AZ) are displayed simultaneously. In addition, in the lower right hand corner will be the abbreviation for the
current constellation that the telescope is pointed at.
Identify: The Identify Mode of Northstar provides the ability to Identify any object within your telescope field of
view. Subcategories for different classes of identifiable objects are included as well as an Identify Any option.
Align Earth: The Align Earth Mode of Northstar provides the ability to easily align your telescope utilizing
common information non-astronomers would readily know. By entering simple information such as time, date,
city, etc. a first time telescope user can be exploring the immense Northstar database of astronomical objects
within minutes.
Align Star: The Align Star Mode of Northstar provides the ability to align your telescope utilizing some
astronomical knowledge. By knowing where two stars are located in the sky, a novice user can circumvent the
city, date, and time input and quickly start utilizing the Northstar database to locate amazing astronomical objects.
Align Object: The Align Object Mode of Northstar provides the ability to refine your telescope alignment during
the middle of your observing session. This might come in very handy if the family dog has just bumped the
telescope out of alignment. By using this mode you can center the telescope on any known object and select
align object to quickly recalibrate the Northstar alignment allowing continued enjoyment for the duration of the
evening.
13.

14.

MALIGNING NORTHSTAR FOR THE FIRST TIME
When you turn the telescope on a scrolling message will appear:
The first display will then prompt you to level the telescope tube. The display will read:
The display will alternate to:
After the tube is leveled and ENTER is pressed, the display will briefly read
Then the default menu will appear:
This mode assumes that even if the telescope user is a first time user and does not know anything about
astronomy that they can be successful aligning the telescope in a few simple steps.
The ALIGN EARTH option is flashing. This indicates that if we press the ENTER key we will then be faced with
the ALIGN EARTH menu.
Press ENTER to choose ALIGN EARTH option.
NOTE: ANY FLASHING ITEM ON THE DISPLAY IS AMENU CHOICE. OTHER CHOICES ARE AVAILABLE
BY USING THE SCROLL UP OR SCROLL DOWN BUTTONS.
STEP1: SET THE TIME
By using the SCROLL UP and SCROLL DOWN buttons and the ENTER button, the time can easily be set as
well as the time zone. Each flashing option will need to be changed to read the appropriate number. Once the
number is displayed, you accept the number by pressing ENTER. Then you would set the next flashing option
until the time and time zone are set.
STEP 2: SET THE DATE
Again by using the SCROLLUPand SCROLLDOWN buttons and the ENTER button, the date can easily be set.
Each flashing option will need to be changed to read the appropriate number or month. Once the number is
displayed, you accept the number by pressing ENTER. Then you would set the next flashing option until the day,
month and year are set.
15.

MALIGNING NORTHSTAR FOR THE FIRST TIME (Continued)
STEP 3: SET THE LOCATION
The next screen will display:
CITY will be flashing. By pressing the ENTER button, the display will change to:
The country will be flashing.
Again by using the SCROLLUP and SCROLLDOWN buttons and the ENTER button, the COUNTRY can be chosen.
When the appropriate Country is found and the ENTER button is pushed, you would finally choose the city that you were
closest to by pressing ENTER when it is displayed.
NOTE: CHOOSE THE CITY CLOSEST TO YOUR VIEWING LOCATION. THIS IS NOTA CRITICALSTEPANDTHE
ALIGNMENT WILLAUTOMATICALLY BE REFINED AS WE PROGRESS.
STEP 4: POINT NORTH
After choosing the city, the display will read:
You would then point the telescope in the direction of North and press ENTER.

MALIGNING NORTHSTAR FOR THE FIRST TIME (Continued)
NOTE: THE USER WOULD JUST HAVE TO GET THE TELESCOPE POINTED RELATIVELY CLOSE TO
NORTH. THE ALIGNMENT WILL BE REFINED AS WE PROGRESS. HOWEVER, IF YOU CAN FIND THE
BIG DIPPER AND USE THE "POINTER STARS", FOLLOW THE ARROW ON THE ABOVE DIAGRAM TO
THE NORTH STAR. THE NORTH STAR LIVES DIRECTLYABOVE DUE NORTH!
After pointing the telescope NORTH and making sure the tube is still pointed level, pressing the ENTER button
would complete the rough alignment process.
Apolite THANK YOU will then be displayed.
After four simple criteria that any consumer should know, the telescope now knows where over 20,000
astronomical objects are in the night sky to a relative precision. With just two more steps, we will zero in on
pinpoint accuracy.
Now the telescope will lead us through a simple two star alignment process. WE DO NOT NEED TO KNOW
WHEREANY STARS ARE. We just simply follow the directions.
Ascrolling message indicates to CENTER STAR 1 THEN PRESS ENTER
Then the display will read:
The user will simply follow the arrows to zero in on this first guide star. Note that this will be the only bright star
in this area of the sky. By following the arrows on the display it will tell us how far away we are from the guide
star. Move the telescope tube with your hands until the display reads:
Note as you move from greater than 10 degrees away from an object to under ten degrees, the display moves
into tenths of degrees with the arrows acting as decimal points (Example below the
object).
After getting the star zeroed in, you need to do as the screen told you—CENTER STAR 1. In other words, the
star might appear in the lower left corner of your telescope’s eyepiece.
By looking through the eyepiece, center the star in the field of view and press ENTER.
The distance the object is from the center is related to how far outside of a city you might be located or how
accurately you aligned with north.
You would then repeat this process for STAR 2 and press ENTER.
After this step is completed, you will see a display that reads:
(Note: The more stars that appear on the second line of the display the better, up to 5)
After the two star alignment is complete, your Northstar now knows with pinpoint accuracy where
all 20,000+ objects are!!
17.

MUSING NORTHSTAR FOR THE FIRST TIME
After EARTH ALIGN, the display will then read:
EXPLORE will be flashing. This indicates that you could choose other options by pressing the
UP and DOWN buttons. However, let’s look at EXPLORE first. This is the default menu at this
point because, this will most likely be the most often used mode. This is where the starfinding
takes place.
Select EXPLORE by pressing ENTER. SCROLL UP and DOWN to see what flashing menu
choices you have. I always choose PLANET. These are the most interesting. Even if you are
a first time telescope user, PLANET objects can be very exciting.
Press ENTER when the display reads:
This will take you into a list of named PLANETobjects. By using the SCROLLUPor SCROLLDOWN buttons,
you can explore several items in the object list.
Press ENTER to choose the PLANET you wish to view. The display would then be:
NOTE: IF AN OBJECT IS BELOW THE HORIZON, THE DISPLAY WILL PERIODICALLY DISPLAY THE
WORD "HORIZON".
SCROLLUPor SCROLLDOWN to see other PLANETS in the list. Notice the display shows you directions to
each object. But what if you are a first time user want to find out more about the object? Wouldn’t it be nice
to know what the object is before moving the telescope?
PRESS ENTER when:
is displayed or any other PLANET item. You will see a scrolling message telling you the coordinates for the
object, how bright it is, how big it is, what its proper name is, what constellation it is in, and a brief description
of what the object is. For JUPITER it would read:
Now imagine that you are a parent trying to impress your kids (or vice versa). Ten minutes into your first
observing session you are already learning astronomical objects.
This is a great educational tool!!!!
To find the object, just follow the directions displayed by the arrows until you zero the object out and it will be
right in the telescope’s eyepiece!
18.

MUSING NORTHSTAR FOR THE FIRST TIME (Continued)
The TELESCOPE mode gives you dynamic real-time information on your telescope’s current position in terms
of astronomical coordinates. Play around with this mode by moving the telescope around. Notice the three letter
abbreviation in the lower right portion of the display. This dynamically displays the current CONSTELLATION
that the telescope is pointing at. These names are abbreviated in this mode. Definitions for the abbreviations
will be in the catalog index.
19.
By pressing the BACK button, you move back to the previous level each time the button is pressed. Press the button
three times and you are back at the main level menu. The display will read:
SCROLLUP or SCROLL DOWN to select
Press ENTER.
This mode will take you through the best and brightest objects for each month. If you have done the ALIGN EARTH
alignment and entered the date, it will automatically take you to the current month. Don’t know what some of these
obscure objects and abbreviations mean? Just press the ENTER key for more information.
Press the BACK button until you get back to the main menu:
SCROLL UP or SCROLLDOWN until the display reads:
PRESS ENTER
This mode will default to the level
By selecting this option with the ENTER key, it will IDENTIFYthe object that you are currently viewing OR the closest
object to where your telescope is currently pointed. You also have the options to choose other types of IDENTIFY
menus. These will IDENTIFY the closest CLUSTERS, NEBULAS, etc. to your current telescope position.
To select the final mode press ENTER at the display:
The display reads something like:

20.
The following appendix information is more thorough information than that listed
in the main instruction manual. For sake of space, the complete 20,000 object
catalog is not listed. However, we have included the entire star list and the entire
Messier object lists for your information. In addition, the constellation
abbreviations are defined that are found in the Northstar system.
Catalog Index